1. Field of the Invention
The present invention relates to a device that controls a hybrid vehicle including an engine and a motor as drive power sources and a hybrid vehicle. The present invention particularly relates to a control device for a hybrid vehicle that is configured such that an engine and a first motor having a power generation function are coupled to a power split mechanism having a differential function and that power generated by the first motor is supplied to a second motor that generates drive power for traveling and to a hybrid vehicle.
2. Description of Related Art
Examples of a hybrid vehicle of this type are described in Japanese Patent Application Publication No. 8-295140 (JP 8-295140 A) and Japanese Patent Application Publication No. 2013-141959 (JP 2013-141959 A). A configuration of such a hybrid vehicle will be described briefly. A planetary gear mechanism of single pinion type is provided as a power split mechanism, an engine is coupled to a carrier thereof, and a first motor generator is coupled to a sun gear thereof. A ring gear serves as an output element and is coupled to a differential via a specified gear train. Then, a second motor generator is coupled to an output shaft thereof, and power that is generated in the first motor generator is supplied to this second motor generator.
In addition, a one-way clutch is provided that is engaged to inhibit reverse rotation (negative rotation) of the engine, the carrier that is coupled thereto, or an engine shaft that connects the engine and the carrier. This one-way clutch inhibits the rotation of the engine, the carrier, or the engine shaft by receiving a reactive force that is generated in conjunction with negative rotation of the first motor generator. As a result, output torque of the first motor generator is transmitted as torque in a positive rotational direction to the ring gear. In other words, it is configured that so-called two-motor EV travel is performed in which the first and second motor generators function as traveling motors during a forward travel. Noted that JP 8-295140 A describes an example in which a brake is provided instead of the one-way clutch.